I currently have CS4 Web Premimum and I an interested in upgrading to the CS6 Creative Cloud. How many computers can I use my subscription for? Currently it is two, but I want to make sure this will still be the case for CS6. Also would my CS4 applications run on alternate computers if I installed it?

One of the Adobe videos notes that a merit of the software is that you can mix and match users. For example if you have a freelancer who needs a copy of CS6 to fit in with your workflow then you can buy a month on month subscription. I imagine this would apply to a yearly subscription if you need to share it about within the licensing constraints. From what I've read you can only have one instance of CS6 "as long as they are not running at the same time". This is the wording of the terms "install them on your primary computer and one backup computer".